Closure system

ABSTRACT

A closure system including a door mounted to open and close an entrance way, and an object detector including a transmitter and detector mounted on the door. The transmitter directs a beam of radiant energy to a sill having a non-specular surface, and the detector is aimed to intersect the beam of radiant energy at the sill. The detector controls the operation of the door when an object interrupts reflected radiant energy from the sill to the detector.

United States Patent 1191 Berkovitz et a1.

[ 1 Dec. 31, 1974 CLOSURE SYSTEM [75] Inventors: Harry Berkovitz,Glenrock;

Lawrence Tosato, Millburn, both of NJ.

[73] Assignee: Westinghouse Electric Corporation,

Pittsburgh, Pa.

[22] Filed: Dec. 18, 1973 [21] Appl. No.: 426,261

[52] US. Cl 187/52, 49/25, 250/221 2,853,158 9/1958 Brandon et a1.187/48 2,953,219 9/1960 Drexler 187/48 Primary ExaminerRichard A.Schacher Assistant Examiner-James L. Rowland Attorney, Agent, or Firm-D.R. Lackey 5 7 ABSTRACT A closure system including a door mounted to openand close an entrance way, and an object detector including atransmitter and detector mounted on the door. The transmitter directs abeam of radiant energy to a sill having a non-specular surface, and thedetector is aimed to intersect the beam of radiant energy at the sill.The detector controls the operation of the 5 References Cited door whenan object interrupts reflected radiant en- UNITED STATES PATENTS ergyfrom the sill to the detector.

1,947,079 2/ 1934 Ellis 187/52 16 Claims, 5 Drawing; Figures 25 33 Q la1 I 27 I 2| e -29 g 13 A15 9 7 9 A21 A7 A9 a) I I 3: n [1 M: I];

H A13 1 5 I: 11

[I l 1 A51 11 l 11 a 1 R70 A17 17 Lass :1 a5 :1 1: 1 '1 1: 1 1 1: l} l 1I T3 T2 {i l: mz i 1 e 1 a 5i CLOSURE SYSTEM BACKGROUND OF THEINVENTION 1. Field of the Invention The invention relates in general toclosure systems, and more specifically to object detecting arrangementsfor closure or door control which are especially suitable for elevatorsystems.

2. Description of the Prior Art Closure control, which includes objectdetecting means for controlling door operation to prevent the door fromstriking an object in the closing path of the door, is in common usage,especially in elevator systems. For example, US Pat. No. 1,947,079teaches a car mounted object detector system which directs a beam ofradiant energy out from the elevator car to a reflector disposed in aglass covered enclosure in the floor of the landing. The reflectorreflects the radiant energy back to a detector mounted on the car.

US. Pat. No. 2,900,521 teaches a plurality of door mounted transmittersand detectors disposed to direct a plurality of horizontal beams ofradiant energy across the door opening of the elevator car.

US. Pat. No. 2,953,219 teaches door mounted transmitters and detectorswhich direct two beams along the edge of the door of the elevator car.

US. Pat. No. 3,063,516 teaches a door mounted object detector whichreflects a beam of radiant energy from one car door to a reflector onthe adjacent hoistway door, across the opening of the elevator car to areflector on the other hoistway door, and then to a detector on theother car door.

In all of these patents, which are assigned to the same assignee as thepresent application, the object detector system either transmits a beamof radiant energy directly from a transmitter to a detector, or thetransmitter transmits the beam of radiant energy against a specularsurface or mirror, with the reflected energy going directly to adetector, or indirectly to a detector via ad ditional reflectors. Whenreflectors are used, the angle of incidence of the transmitted beam ofradiant energy to the normal of the reflector, and the angle ofreflection, are equal. In specular or regular reflection, the directionof propagation of the energy of the concentrated beam is still sharplydefined after reflection, the reflected and incident beams of radiantenergy travel in directions making equal angles with the normal to thereflecting surface, and the transmitted beam, the reflected beam, andthe normal of the reflecting surface, all lie in the same plane.

While the arrangements of these patents are all effective objectdetectors, they are limited as to the locations of the beams of radiantenergy by the requirement of directly aiming the detector at thetransmitter, or by the requirement of placing the transmitter anddetector according to the characteristics of specular reflection, whenreflectors are used.

SUMMARY OF THE INVENTION Briefly, the present invention is a new andimproved closure system having an object detector which uses atransmitter, a detector, and a reflector, with the reflector being asill associated with the entranceway of the closure system. The sill isnot a reflector in the usual sense, as it is important that its surfacebe nonspecular. The transmitter directs a focused beam of radiant energyto the sill, and the detector is aimed to intersect the beam at thesill. The non-specular surface of the sill produces a diffusereflection, i.e., scattered, a certain portion of which will proceedfrom the sill to the detector which is aimed at the location on the sillto which the beam of radiant energy is directed. The detector isadjusted to be responsive to the level of the reflected energy such thatit detects when the reflected energy is blocked by an object in the pathbetween the spot" on the sill to which the detector is aimed, and thedetector.

The locations of the transmitter and detector are not limited by theequal angles of incidence and reflection, which is characteristic ofspecular reflection, nor are their locations limited to the same planelimitations of specular reflection.

In a preferred embodiment of the invention, the new and improved closuresystem is used in an elevator system to provide an edge detector foreach hoistway door, using primarily car mounted apparatus. In thispreferred embodiment, the transmitter and detector are both mounted onthe door of the elevator car, and at least one beam of radiant energy isprojected from the transmitter to a sill disposed at the landing. Thissill extends past the hoistway door, when it is closed, on the corridorside of the landing. At least the portion of the sill which is on thecorridor side of the hatchway door has a non-specular surface. The beamof radiant energy is projected to this portion of the sill, and thereflection of radiant energy to a detector mounted on the car doorprovides a reflective path which extends past the leading edge of thehoistway door to provide an object detector immediately adjacent theleading edge of the hoistway door upon closure thereof. A plurality ofradiant beams may be used to provide several object detection zonesadjacent the leading edge of the closing hoistway door. Similar edgeprotection may be provided for the leading edge of a closing car door.

BRIEF DESCRIPTION OF THE DRAWINGS The invention may be betterunderstood, and further advantages and uses thereof more readilyapparent, when considered in view of the following detailed descriptionof exemplary embodiments, taken with the accompanying drawings, inwhich:

FIG. 1 is a view in front elevation of an elevator car having a closuresystem embodying the invention;

FIG. 2 is a fragmentary side elevation of the closure system shown inFIG. 1;

FIG. 3 is a fragmentary plan view of the closure system shown in FIG. 1;

FIG. 4 is a schematic diagram of door control which may be used foroperating the closure system shown in FIG. 1; and

FIG. 5 is a fragmentary plan view which illustrates a modification ofthe closure system shown in FIGS. 1, 2 and 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS While the invention isapplicable to closure designed for various applications, it isespecially suitable for doors employed in elevator systems. Thus, theinvention will be described with particular reference to elevatorclosures or doors. Further, the invention is applicable to doors ofvarious types, such as center opening, side opening, single speed, andtwo speed assemblies.

For purposes of example, reference will be made to door assemblies ofthe center opening, power operated type, such as employed in elevatorsystems. In order to simplify its presentation, the invention is assumedto be applied to an elevator car employing the center opening,horizontally slidable doors, and controls therefor, as illustrated inUS. Pat. No. 2,992,818, which patent is assigned to the same assignee asthe present application. Only the portion of the controls of this patentnecessary to understand the invention will be described. If thedescription of the complete control is desired, reference may be had tothis patent for a detailed description.

Referring now to the drawings, and FIG. 1 in particular, there is shownan elevator system 1 which includes an elevator car 2 mounted formovement in the hoistway 3 of an associated building or structure toserve the landings or floors therein. FIG. 1 is a front elevational viewof the elevator car 2 which is illustrated parked at a landing with itsdoors open. The associated hoistway or hatch doors which close andexpose the opening to the hoistway from the associated landing are notshown in FIG. 1, for clarity.

The elevator car 2 includes center opening car doors, shown fully open,with the car doors comprising two sections 5 and A5. A number of similarcomponents are employed for the door sections 5 and A5. Insofar as ispracticable, a component for the door section A5 which is similar to acomponent for the door section 5 will be identified by the samereference numeral as is employed for the corresponding componentassociated with the door section 5 prefixed by the letter A.

The door section 5 is provided with a door hanger 7 on which door hangerwheels 9 are mounted for rotation. The door hanger wheels for the doorsections 5 and A5 are positioned for movement along ahorizontally-mounted track 11 in a conventional manner. The track 11 issecured to the elevator car by any suitable means.

Movement of the door section 5 is effected by a lever 13 pivotallymounted on the elevator car by means of a pin 15. The lower end of thelever 13 is pivotally connected to one end of a link 17, the other endof the link being pivotally connected to the door section 5. The lever13 is coupled to the lever A13 by a link 19, the ends of which arepivotally attached to the levers 13 and A13 by pivots 21 and A21,respectively. The pivot 21 is positioned above the pin 15, whereas thepivot A21 is located below the pin A15. Consequently, rotation of thelever 13 to close the door section 5 moves the link 19in the properdirection to close the door section A5.

The lever 13 preferably is operated by a suitable door operator 23 whichmay include a reversible electric motor 25 coupled through suitablegearing to a shaft 27. The shaft 27 carries an arm 29 which is pivotallyconnected to one end of a link 31, the remaining end of the link 31being pivotally connected to the lever 13. Consequently, the motor 25may be energized in a conventional manner for the purpose of opening andclosing the door sections 5 and A5. When the door 1 is to be opened, themotor 25 is operated to rotate the arm 29 in a clockwise direction asviewed in FIG. 1. In order to reclose the door, the electric motor isreversed.

A control assembly 33 is mounted on the elevator car adjacent the motor25. Positive driven contact cams located in the control assembly 33control the rate of acceleration and deceleration of the door I. Thecontrol assembly also houses control contacts and control resistors. Thecontact cams are keyed to the gearing associated with the motor 25 andoperate the control contacts for predetermined distances of travel ofthe arm 29 to vary motor armature circuit resistance, thus controllingthe doors rate of acceleration and of deceleration. Each cam issymmetrical and operates two spring-closed contacts, one contact beinglocated on each side of the cam. For each direction of door movement, aseparate and identicalset of contacts is actuated, one for the openingmovement of the door, the other for the closing movement of the door.Such arrangement is well known in the art.

The car door sections 5 and A5 are associated with hoistway doorsections 34 and A34, respectively, best shown in FIG. 3. The hoistway orhatchdoor sections 34 and A34 are operable for opening and closing an entrance way to the hoistway. Although the hoistway door sections may beoperated by any conventional door operator, the hoistway sections arepreferably operated by the door operator 23 mounted on the elevator car2 via cooperative vane and drive block members 35 and 36, respectively.The vane 35 is secured to the car door section 5 and is adapted forreception in a slot of the drive block 36, which is secured to thehoistway door section 34. A suitable linkage (not shown), similar tothat disposed between the car door sections 5 and A5, is providedbetween the hoistway door sections 34 and A34. Thus, operation of thedoor operator mounted on the elevator car effects movement of both thecar and hoistway door sections in unison.

During the closing operation of the car and hoistway doors it is highlydesirable that the door sections be prevented from striking an objectlocated in the closing paths thereof. Further, it is desirable that suchprotection include an edge protector or safety edge on the leading edgeof each door section upon closure thereof. It is common to provide suchedge protection on the car door, but-providing object protecting meansfor the edges of the hoistway doors is costly, since each hoistway doormust be outfitted with such door edge devices. Not only is the directcost proportional to the number of hoistway doors in the elevatorsystem, but the maintenance problem associated with such detectingapparatus will also be directly proportional to the number of hoistwaydoors. The present invention provides door edge object detecting meanson the hoistway doors without any apparatus being required for eachhoistway entrance, other than a non-specular surface adjacent thehoistway opening, such as a sill having a non-specular surface. The dooredge object detector for the hatch door is thus achieved with verylittle equipment required for a hoistway door, and little additionalmaintenance.

FIGS. 1, 2 and 3 illustrate front, side and plan views, respectively, ofobject detecting means constructed according to the teachings of theinvention. The object detecting means includes transmitter means 60 anddetector means 62 associated with the left hand car and hoistway doorsections 5 and 34, respectively, as viewed in FIG. 1 and transmittermeans 64 and detector means 66, associated with the right hand car andhoistway door sections A5 and A34, respectively. Since the arrangementand operation of the object detecting means is similar for the left andright hand door sections, only the object detecting means for the lefthand door sections will be described in detail.

Transmitter means 60 is mounted on car door section 5, preferablytowards the bottom thereof, and adjacent to the leading edge of the doorwith reference to the closing direction of the door. Transmitter means60 is arranged to provide at least one beam of radiant energy, andpreferably at least two as illustrated in the fig ures, with first andsecond radiant beams 68 and 70 being provided by transmitter devices T1and T2, respectively.

Transmitter devices T1 and T2 are positioned to direct or project theradiant beams 68 and 70 across the small opening 72 between the elevatorcar 2 and the hoistway wall 3 to the sill 74 associated with thehoistway entrance. At least one of the beams, such as beam 68, isdirected to strike the sill 74 on the corridor side of the hoistway door34, as opposed to the hoistway side, and the other beam is projected tostrike the sill substantially adjacent to the edge of the hoistway door34. The corridor is indicated with reference numeral 76 in FIG. 3. Thebeams 68 and 70 of radiant energy are directed to predetermined spots orlocations on the sill 74, indicated at 78 and 80, respectively, whichlocations will move across the sill 74 with movement of the car andassociated hatch door sections 5 and 34 respectively. In order toproject the beams of radiant energy across the opening between theelevator car and hoistway wall to the corridor side of the sill 74, itmay be necessary to remove a small portion of the sight guard (notshown) which blocks the view into the space between the car 2 andhoistway wall 3. However, since it is only necessary to remove the sightguard close to the floor level, it will not be noticeable to prospectivepassengers.

It is important to note that at least the portions of the sill 74 towhich the beams 68 and 70 of radiant energy are directed throughoutmovement of their associated car door section, be formed of a materialwhich has a non-specular surface and which will not become polished orspecular during use. A sill constructed of a fairly rough bronze, i.e.,unpolished, has been found to be satisfactory, but any material may beused which will scatter the reflection of the beam of energy from itssurface, instead of reflecting the beam with a sharply definedprojection. A sill formed of a metallic grit, such as aluminum oxide,held together with a suitable binder, such as epoxy resin, is alsosuitable, as the small metallic particles uniformly scatter thereflection of the beam of radiant energy from its surface.

Detector means 62, which is sensitive to the level of the reflectionwhich will be received from the sill 74, includes the same number ofdetector devices as there are radiant beams to detect. In other words,when two transmitters, T1 and T2 are used to transmit two beams 68 and70, detector means 62 will include two detectors D1 and D2. Detectormeans 62 is mounted for movement with car door section 5, and eachdetector device of detector means 62 is aimed to intersect a beam ofradiant energy at the sill 74. Thus, as shown most clearly in FIG. 3,the detector device D1 would be aimed at the spot or location 78 on thesill 74, and detector device D2 would be aimed at spot or location 80 onthe sill. A suitable detector is Photo-hell's side sensitive receivertype RPS3R.

Detector means 62 is mounted at the top of the car door 5 with detectordevice D1 spaced from the edge of the door 5, such as about 3 inches,and with detector device D2 spaced from the edge of the door 5, such asabout one-half inch. The reflection path from spot 80 to detector deviceD2, indicated by beam Rin FIG. I, proceeds past the edge of the hoistwaydoor about one-half inch therefrom. Therefore, an object such as a handplaced on the edge of the hoistway door 34 will interrupt the reflectionfrom spot to detector D2, and this interruption initiates a controlaction in the door control circuit to retard further closing movement,and to reverse the doors, if desired. The reflection path from spot 78to detector Dl, indicated by beam R68 in FIG. 1, proceeds past the edgeof the hoistway door, about 3 inches therefrom, and extends the objectdetection zone out to the point where detection of an object providestime for the closing door to stop without contact with the person orobject interrupting this reflection.

It will be noted in FIGS. 1, 2 and 3 that the detectors D1 and D2 arenot placed such that the angle of reflection from the sill is equal tothe angle of incidence of the beams the detectors are to cooperate with,and that the angle of reflection is not in the same plane as the angleof incidence of the beams and the normal to the sill 74. Thisarrangement is made possible by the nonspecular surface of the sill,enabling the reflections to be directed to locations for objectdetecting not heretofore possible. Thus, edge detectors are provided onthe leading edges of the hoistway doors upon closure thereof, withoutthe necessity of adding apparatus to each hoistway door.

The object detecting means for the right hand door sections are similarto those for the left hand door sections, with the transmitter meansincluding transmitter device T3 and T4, directed to spots A78 and A80 onsill 74, and the detector means 66 includes detectors D3 and D4 aimed atspots A78 and A80, respectively.

It will be noted in FIG. 3, that detector devices 62 and 66 are offsetfrom one another to permit them to pass upon closure of the doors. The 3inch" detectors D1 and D3 are rendered ineffective by a limit switch Lldisposed to cutout these detectors just before they would detect aninterruption of the reflected energy due to normal door closure, and theone-half inch" detectors D2 and D4 are rendered ineffective by a limitswitch L2.

The radiant energy projected by the transmitting device 60 may have afrequency selected from a widerange. For example, the transmittingdevice may be designed to project visible light. However, since numeroussources of light are present both within the elevator car and in thecorridors served by the elevator car, the possibility of false operationof the apparatus due to these external sources is present; and if anattempt is made to shield the detecting means 62 from other lightsources, it becomes difficult to clean and to maintain the detectingdevice. For these and other reasons, nonvisible radiant energy isdesirable.

Preferably, the transmitting device 60 is designed to transmit a beam ofinfrared radiant energy. Such devices are well known in the art. Thedetecting device 62 may be of any type responsive to the radiant energyreceived from the transmitting device 60. Thus, for infrared radiantenergy the detecting device 62 may be of the photoemissive type, thephotoconductive type or the photovoltaic type, as desired. Suchdetecting devices also are well known. Reference may be made to theEames US. Pat. No. 2,900,521 for details of construction of suitableradiant energy transmitting and detecting devices.

In order to illustrate suitable operation of the door controller 33, aschematic control diagram is shown in FIG. 4. In this diagram, thearmature 25A and the field winding 25F of the door operating motor 25(FIG. 1) are illustrated. Electrical energy for the control circuits isderived from a pair of direct-current buses L+ and L-. It will beobserved that the motor field winding 25F is connected directly acrossthe buses L+ and L. In parallel with the field winding 25F is arectifier 90 of a conventional type, such as silicon. Current flowsthrough the rectifier 90 in the direction indicated by its circuitsymbol in FIG. 4. Thus the rectifier 90 provides a path for inducedcurrent as a result of the collapse of the motor field windings magneticfield in the event that power is removed from the buses L+ and L.

The motor 25 is energized to open or to close the car door by operationof a switch SW. Although this may be a manually operated switch, in apreferred embodiment of the invention this switch represents thecontacts of a relay or relays employed in any conventional dooroperating system to initiate an opening or a closing operation of thedoor. Thus, movement of the operating member of the switch SW up, asviewed in FIG. 4, to close its contacts SW1, completes, with a limitswitch 37 and break contacts CLl of a door closing relay, CL, a circuitconnecting a door opening relay OP across the buses L+ and L forenergization. The limit switch 37 is opened as the door arrives at itsfully open position by a cam located in the control assembly 33.

Movement of the operating member of the switch SW down results inclosure of its contacts SW2 to complete, with a limit switch 39 andbreak contacts 0P1 of the door opening relay OP, a circuit connectingthe door closing relay CL across the buses L+ and L for energization.The limit switch 39 is opened as the door arrives at its fully closedposition by a cam located in the control assembly 33.

The break contacts CLl prevent energization therethrough of the dooropening relay OP when the door closing relay CL is energized. The breakcontacts OP] operate in a similar manner in the circuit of the doorclosing relay CL. Also associated with the relay OP are make contacts0P2 and 0P4 and break contacts 0P3. Associated with the relay CL aremake contacts CL2 and CL4 and break contacts CL3. These contacts controlenergization of the motor armature 25A, the circuits for energization ofthe armature being located in the lower portion of FIG. 4.

Associated with the armature 25A are a plurality of adjustable resistorsand a plurality of cam-operated control contacts for controllingacceleration and deceleration of the motor 25. These resistors andcontacts, together with the contact cams for the latter, are located inthe control assembly 33 as above described.

It will be noted that the adjustable resistor 41 is dis posed in seriescircuit relationship with the armature 25A in the bus L+. The remainderof the adjustable resistors associated with the armature 25A bearidentifying symbols which are indicative of their functions. Thus, theadjustable resistor RAC is employed to effect acceleration of the motorduring a door closing operation while the adjustable resistor RAO isemployed for accelerating the motor during door opening movement.

Similarly, the resistor RDCl is used for decelerating the motor andthereby the door during a door closing movement while the adjustableresistor RDOl effects deceleration. The cam operated control contactsbear identifying symbols which are indicative of their controlfunctions. For example, the contacts AC and A0 are effective foraccelerating the door during door closing and door opening movements,respectively. The contacts DCl through DC4 effect deceleration of thedoor during door closing movement and operate sequentially in the orderof their suffix numerals. The contacts DOl through D04 in sequencesimilarly control door deceleration during a door opening operation.

Make contacts ASC and AS0 are disposed in series circuit relationshipwith the cam-operated contacts DC4 and D04, respectively. These contactsare associated with an anti-stall or checkback relay AS. If a pair oflimit switches 43 and 45 both are in closed condition, the relay AS isconnected for energization across the buses L+ and L. In parallel withthe coil of the relay AS is a resistor-capacitor network comprisingserially connected resistors 47 and 49 and a capacitor 51. In parallelwith the resistor 47 is a rectifier 53 of a conventional type such assilicon. Current flows through the rectifier 53 in the directionindicated by its circuit symbol in FIG. 4. Thus, when both of the limitswitches 43 and 45 are in closed condition, the capacitor 51 chargesthrough the resistor 49 and the rectifier 53, which, in effect, thenshorts the resistor 47. When one of the limit switches 43 or 45 isopened, the capacitor 51 discharges through the resistors 47 and 49 andthe coil of the anti-stall relay AS. Since the length of times of chargeand discharge of the capacitor are dependent upon the RC network timeconstant, the rectifier 53 effects a fast charge of the capacitor 51 anda relatively slow discharge thereof.

The limit switches 43 and 45 are located in the control assembly 33 andare operated by cams disposed therein. In a preferred embodiment of theinvention, the cam associated with the switch 43 operates to open theswitch simultaneously with the opening of the control contacts DC4 byits associated contact cam. The limit switch 45 is opened by its camsimultaneously with the opening of the control contacts D04 by itassociated contact cam. Each of these limit switches remains in openconditon from the time of its opening to the time when the door reachesthe same position in a door movement opposite in direction to that inwhich the door was moving when the respective limit switch was operatedby its associated cam.

The present invention modifies the circuit of the aforesaid US. Pat. No.2,992,818 by connecting the energizing coil of a door safety relay DRbetween buses L+ and L via serially connected contacts B1, B3, B2 andB4. Contacts B1, B3, B2 and B4 are associated with detectors D1, D3, D2and D4, respectively, with these contacts being directly controlled byany suitable translating device associated with the detectors. Such atranslating device may take the form of relays whose energizing coilsare not shown. Contacts B1, B2, B3 and B4 are closed as long as itsassociated detector device is receiving radiant energy from the spot onthe sill 74 to which it is aimed. Limit switches L1 and L2 shown in FIG.4 are connected to shunt or short contacts B1 and B3, and B2 and B4,respectively, to render these contacts ineffective when the doors close.Door safety relay DR includes a make contact DR] which is connected inseries with the energizing coil of the closing relay CL, and breakcontacts DR2 connected to shunt contacts SW1 of switch SW. It should benoted that the contacts DR! and DR2 are shown in the condition whenbuses L+ and L are deenergized. When the door is closing and noobstruction is detected by any of the detectors, relay DR will beenergized. Thus, contacts DRl will be closed to enable the closing coilCL to be energized, and contacts DR2 will be open, and they will thushave no circuit affect on the door open relay OP. Should reflection ofradiant energy to any of the detector devices be interrupted, itsassociated contact would be open, such as contact Bl, which drops outthe door safety relay DR. Contacts DR] open to deenergize the coil CL ofthe closing relay and stop the closing motion of the car and hoistwaydoors, and contacts DR2 close to energize the door open relay OP. Shouldit only be desired to stop the closing of the doors upon interruption ofradiant energy from the sill to one of the detectors, instead ofreversing the doors, contacts DR2 would not be required. When the doorsreach the point during closing where reflection from the sill will beinterrupted by the opposite door section, limit switches L1 and L2successively operate to first disable the 3 inch detectors, and then theone'half inch detectors. It is to be understood that while thesedetectors are referred to as the 3 inch and one-half inch detectors,that their loca tions may be changed from these dimensions, if desired.

FIG. 5 is a fragmentary plan view, similar so that of FIG. 3, exceptmodified to illustrate that the detector means 64 may direct twoadditional beams of radiant energy to the sill 96 of the elevator car,indicated by spots A92 and A94, and the detector means includes twoadditional detectors D5 and D6 aimed to intersect the beams at spots A92and A94, respectively, thus providing object detecting means immediatelyadjacent the leading edges of the car door, as well as the hatch door.Contacts associated with detectors D5 and D6, as well as the additionaldetectors for the left hand door section, would be connected in serieswith the door safety relay DR, as illustrated for the contacts 81through B4.

in summary, there has been disclosed a new and improved closure system,in which placement of the transmitter and detector devices is notlimited by the characteristics of specular reflection. In a preferredembodiment of the invention, the new and improved closure system is usedin an elevator system to provide edge detection for the hoistway doors,without requiring transmitters and detectors for each hoistway opening.The transmitters and detectors are all mounted on the car, requiringonly a sill having a non-specular surface at each hoistway opening. Thenew and improved closure system thus permits edge protection forhoistway and car doors, without requiring a mechanical edge with itsmaintenance problems, and the elimination of the mechanical safety edgeincreases the opening size. Further, the new and improved closure systemis sensitive to any object in the path of the closing doors, and is notlimited to detecting objects having a certain amount of capacitance.

We claim as our invention:

1. A closure system, comprising:

an entranceway,

a sill associated with said entranceway, at least a portion of said sillhaving a non-specular surface,

a door for said entranceway,

means mounting said door for movement to open and close saidentranceway,

an object detecting means including transmitter means providing at leastone beam of radiant energy, and detector means responsive to suchenergy,

said transmitter means being mounted on said door for movement therewithand positioned to direct a beam of radiant energy at said non-specularsur' face of the sill, said beam of radiant energy forming apredetermined angle with the normal of said sill,

said detector means being mounted on said door for movement therewithand positioned to intersect said beam of radiant energy at said sill,with the angle of reflection from the :sill to said detector meansrelative to the normal thereof, being other than said predeterminedangle,

said detector means being responsive to an interruption of reflectedradiant energy from said sill for controlling the operation of saiddoor.

2. The closure system of claim 1 wherein the angle of reflection of theradiant energy from the sill to the detector means forms a plane withthe angle of incidence of the beam of radiant energy which is differentthan the plane that would be formed between the same angle of incidenceand the angle of reflection from a specular surface.

3. The closure system of claim 1 wherein the radiant energy whichreflects from the sill to the detector means is spaced from andsubstantially parallel to the leading edge of the door upon closurethereof.

4. The closure system of claim I wherein the transmitter means providesa plurality of spaced beams of radiant energy which are directed at thenon-specular surface of the sill, with the detector means including aplurality of detector devices aimed to intersect a different beam ofradiant energy at the sill, with the radiant energy which reflects fromthe sill to the plurality of detector devices being spaced from andsubstantially parallel to the leading edge of the door upon closurethereof, to provide a plurality of spaced object detecting locations.

5. An elevator system, comprising:

a structure having a hoistway, a landing having an opening to thehoistway, and a sill at the landing adjacent the opening, said sillhaving a nonspecular surface,

an elevator car mounted for movement in the hoistway of said structureto serve said landing,

said elevator car having an opening therein which is in registry withthe opening to the hoistway when said elevator car is at said landing,

a car door mounted for movement to open and close the opening of saidelevator car,

a hoistway door mounted for movement with said car door to open andclose the opening to the hoistway,

and object detector means including transmitter means providing at leastone beam of radiant energy, and detector means responsive to suchenergy,

said transmitter means being mounted on said car door for movementtherewith and positioned to direct a beam of radiant energy at saidnon-specular surface of the sill,

said detector means being mounted on said car door for movementtherewith and aimed to intersect the beam of radiant energy at saidsill,

said detector means being responsive to an interruption of reflectedradiant energy from said sill for controlling the operation of said carand hoistway doors.

6. The elevator system of claim wherein the transmitter and detectormeans are oriented such that reflected radiant energy from the sill tothe detector means is spaced from and substantially parallel to theleading edge of the hoistway door upon closure thereof.

7. The elevator system of claim 5 wherein the sill includes a portionwhich extends past the side of the hatch door which is opposite to theside which faces the opening, with the beam of radiant energy beingdirected to this portion of the sill, and the detector means is disposedsuch that the reflected radiant energy from the sill to the detectormeans is spaced from and substantially parallel to the leading edge ofthe hoistway door upon closure thereof.

8. The elevator system of claim 5 wherein the transmitter means directsa plurality of spaced beams of radiant energy at the non-specularsurface of the sill, the detector means includes a plurality of detectordevices each aimed to intersect a different beam of radiant energy atthe sill, said plurality of detector devices being disposed such thatthe reflected radiant energy from the sill to the detector devicesprovides a plurality of spaced object detection locations adjacent tothe leading edge of the hoistway door upon closure thereof.

9. The elevator system of claim 5 wherein the elevator car includes asill adjacent its opening, at least a portion of which has anon-specular surface, the transmitter means directs at least one beam ofradiant energy at the car sill in addition to the at least one beamwhich is directed to the landing sill, and the detector means includesfirst and second detector devices aimed to intersect the beams ofradiant energy at the car and hatch sills, respectively, said detectormeans controlling the operation of the car and hatch doors whenreflection of the radiant energy to either detector device isinterrupted.

10. An elevator system, comprising:

a structure having a hoistway and a landing having an opening to thehoistway,

an elevator car mounted for movement in the hoistway of said structureto serve said landing,

said elevator car having an opening therein which is in registry withthe opening to the hoistway when said elevator car is at said landing,

a car door,

means mounting said car door for movement to open and close the openingin said elevator car,

object detector means including transmitter means providing at least onebeam of radiant energy, and detector means responsive to such radiantenergy, said transmitter means being mounted on said car door andpositioned to direct at least one beam of radiant energy to apredetermined location on said landing, with the predetermined locationat any instance depending on the instantaneous position of said cardoor,

the predetermined location on said landing to which one beam of radiantenergy is directed having a non-specular surface, said detector meansbeing mounted on said car door and oriented to the same predeterminedlocation of said landing to which the transmitter device is directingthe at least one beam of radiant energy,

said detector means being operatively connected to control the operationof said car door, in response to the interruption of the reflection ofthe at least one beam of radiant energy from the non-specular surface ofthe location on said landing to said detector means.

11. The elevator system of claim 10 wherein the landing includes a silladjacent the opening to the hoistway, and wherein the predeterminedlocation to which the transmitter directs the beam of radiant energy atany instance is on said sill.

12. The elevator system of claim 10 wherein the landing includes ahoistway door, means mounting the hoistway door to open and close theopening to the hoistway with like movement of the car door, and a silldisposed at the landing adjacent the opening to the hoistway, whereinthe predetermined location to which the transmitter directs the beam ofradiant energy at any instant is on said sill, and the detector means ispositioned on the car door to be responsive to an object in the path ofat least the hoistway door when it is closing its associated openings.

13. The elevator system of claim 12 wherein the sill is disposed suchthat at least a portion thereof is on the side of the hatch dooropposite to the opening to the hoistway, and wherein the transmittermeans is positioned on the car door to direct the beam of radiant energyto said portion of the sill, such that the detector means, oriented tosaid portion of the sill, is responsive to an object in the path of thehoistway door.

14. The elevator system of claim 11 wherein the detector means is aimedat the sill along but spaced from, the leading edge of the hoistway doorupon closure thereof.

15. The elevator system of claim 10 wherein the transmitter meansdirects its plurality of separate, spaced beams of radiant energy topredetermined different locations on said landing, all of whichlocations are on portions of the landings having the non-specularsurface, with the detector means being responsive to the interruption ofthe reflection of any said plurality of beams to the detector means.

16. The elevator system of claim 15 wherein the detector means includesseparate detector devices each aimed along the leading edge of thehoistway door at the different predetermined locations to which theplurality of beams of radiant energy are directed, said separatedetector devices all being mounted on the car door and spaced along theopening to the elevator car to provide a plurality of spaced objectdetector locations adjacent the leading edge of the hoistway door uponclosure thereof.

1. A closure system, comprising: an entranceway, a sill associated withsaid entranceway, at least a portion of said sill having a non-specularsurface, a door for said entranceway, means mounting said door formovement to open and close said entranceway, an object detecting meansincluding transmitter means providing at least one beam of radiantenergy, and detector means responsive to such energy, said transmittermeans being mounted on said door for movement therewith and positionedto direct a beam of radiant energy at said non-specular surface of thesill, said beam of radiant energy forming a predetermined angle with thenormal of said sill, said detector means being mounted on said door formovement therewith and positioned to intersect said beam of radiantenergy at said sill, with the angle of reflection from the sill to saiddetector means relative to the normal thereof, being other than saidpredetermined angle, said detector means being responsive to aninterruption of reflected radiant energy from said sill for controllingthe operation of said door.
 2. The closure system of claim 1 wherein theangle of reflection of the radiant energy from the sill to the detectormeans forms a plane with the angle of incidence of the beam of radiantenergy which is different than the plane that would be formed betweenthe same angle of incidence and the angle of reflection from a specularsurface.
 3. The closure system of claim 1 wherein the radiant energywhich reflects from the sill to the detector means is spaced from andsubstantially parallel to the leading edge of the door upon closurethereof.
 4. The closure system of claim 1 wherein the transmitter meansprovides a plurality of spaced beams of radiant energy which aredirected at the non-specular surface of the sill, with the detectormeans including a plurality of detector devices aimed to intersect adifferent beam of radiant energy at the sill, with the radiant energywhich reflects from the sill to the plurality of detector devices beingspaced from and substantially parallel to the leading edge of the doorupon closure thereof, to provide a plurality of spaced object detectinglocations.
 5. An elevator system, comprising: a structure having ahoistway, a landing having an opening to the hoistway, and a sill at thelanding adjacent the opening, said sill having a non-specular surface,an elevator car mounted for movement in the hoistway of said structureto serve said landing, said elevator car having an opening therein whichis in registry with the opening to the hoistway when said elevator caris at said landing, a car door mounted for movement to open and closethe opening of said elevator car, a hoistway door mounted for movementwith said car door to open and close the opening to the hoistway, andobject detector means including transmitter means providing at least onebeam of radiant energy, and detector means responsive to such energy,said transmitter means being mounted on said car door for movementtherewith and positioned to direct a beam of radiant energy at saidnon-specular surface of the sill, said detector means being mounted onsaid car door for movement therewith and aimed to intersect the beam ofradiant energy at said sill, said detector means being responsive to aninterruption of reflected radiant energy from said sill for controllingthe operation of said car and hoistway doors.
 6. The elevator system ofclaim 5 wherein the transmitter and detector means are oriented suchthat reflected radiant energy from the sill to the detector means isspaced from and substantially parallel to the leading edge of thehoistway door upon closure thereof.
 7. The elevator system of claim 5wherein the sill includes a portion which extends past the side of thehatch door which is opposite to the side which faces the opening, withthe beam of radiant energy being directed to this portion of the sill,and the detector means is disposed such that the reflected radiantenergy from the sill to the detector means is spaced from andsubstantially parallel to the leading edge of the hoistway door uponclosure thereof.
 8. The elevator system of claim 5 wherein thetransmitter means directs a plurality of spaced beams of radiant energyat the non-specular surface of the sill, the detector means includes aplurality of detector devices each aimed to intersect a different beamof radiant energy at the sill, said plurality of detector devices beingdisposed such that the reflected radiant energy from the sill to thedetector devices provides a plurality of spaced object detectionlocations adjacent to the leading edge of the hoistway door upon closurethereof.
 9. The elevator system of claim 5 wherein the elevator carincludes a sill adjacent its opening, at least a portion of which has anon-specular surface, the transmitter means directs at least one beam ofradiant energy at the car sill in addition to the at least one beamwhich is directed to the landing sill, and the detector means includesfirst and second detector devices aimed to intersect the beams ofradiant energy at the car and hatch sills, respectively, said detectormeans controlling the operation of the car and hatch doors whenreflection of the radiant energy to either detector device isinterrupted.
 10. An elevator system, comprising: a structure having ahoistway and a landing having an opening to the hoistway, an elevatorcar mounted for movement in the hoistway of said structure to serve saidlanding, said elevator car having an opening therein which is inregistry with the opening to the hoistway when said elevator car is atsaid landing, a car door, means mounting said car door for movement toopen and close the opening in said elevator car, object detector meansincluding transmitter means providing at least one beam of radiantenergy, and detector means responsive to such radiant energy, saidtransmitter means being mounted on said car door and positioned todirect at least one beam of radiant energy to a predetermined locationon said landing, with the predetermined location at any instancedepending on the instantaneous position of said car door, thepredetermined location on said landing to which one beam of radiantenergy is directed having a non-specular surface, said detector meansbeing mounted on said car door and oriented to the same predeterminedlocation of said landing to which the transmitter device is directingthe at least one beam of radiant energy, said detector means beingoperatively connected to control the operation of said car door, inresponse to the interruption of the reflection of the at least one beamof radiant energy from the non-specular surface of the location on saidlanding to said detector means.
 11. The elevator system of claim 10wherein the landing includes a sill adjacent the opening to thehoistway, and wherein the predetermined location to which thetransmitter directs the beam of radiant energy at any instance is onsaid sill.
 12. The elevator system of claim 10 wherein the landingincludes a hoistway door, means mounting the hoistway door to open andclose the opening to the hoistway with like movement of the car door,and a sill disposed at the landing adjacent the opening to the hoistway,wherein the predetermined location to which the transmitter directs thebeam of radiant energy at any instant is on said sill, and the detectormeans is positioned on the car door to be responsive to an object in thepath of at least the hoistway door when it is closing its assOciatedopenings.
 13. The elevator system of claim 12 wherein the sill isdisposed such that at least a portion thereof is on the side of thehatch door opposite to the opening to the hoistway, and wherein thetransmitter means is positioned on the car door to direct the beam ofradiant energy to said portion of the sill, such that the detectormeans, oriented to said portion of the sill, is responsive to an objectin the path of the hoistway door.
 14. The elevator system of claim 11wherein the detector means is aimed at the sill along but spaced from,the leading edge of the hoistway door upon closure thereof.
 15. Theelevator system of claim 10 wherein the transmitter means directs itsplurality of separate, spaced beams of radiant energy to predetermineddifferent locations on said landing, all of which locations are onportions of the landings having the non-specular surface, with thedetector means being responsive to the interruption of the reflection ofany said plurality of beams to the detector means.
 16. The elevatorsystem of claim 15 wherein the detector means includes separate detectordevices each aimed along the leading edge of the hoistway door at thedifferent predetermined locations to which the plurality of beams ofradiant energy are directed, said separate detector devices all beingmounted on the car door and spaced along the opening to the elevator carto provide a plurality of spaced object detector locations adjacent theleading edge of the hoistway door upon closure thereof.